Food preparation and storage device

ABSTRACT

A food storage and preparation device ( 10, 50, 100, 200 ) is provided for more rapidly cooling or heating a mass of food or other product contained within a storage pan. The device includes a plurality of air contact fins ( 20 ) which rapidly convey heat to and from the ambient surrounding air and a plurality of food contact fins ( 22, 56, 106 ) which are inserted within the mass of food to increase the surface area of the food exposed to a heat transfer surface to more rapidly transfer heat to or from the mass of food.

This application is a continuation of Ser. No. 08/919,526 filed Aug. 28,1997 now U.S. Pat. No. 6,109,345.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the preparation and storage of food and othermaterials of a commercial and industrial nature such as cosmetics,pharmaceuticals and other organic and inorganic materials, and inparticular to a device for rapidly cooling and heating food.

BACKGROUND OF THE INVENTION

In the food preparation industry, the rapid cooling or heating of foodis very critical. For example, when a large batch of food is prepared,for example, a stew, beans or the like, health food regulations, andsafety requires the food to be cooled within a certain time period fromthe cooking temperature, (perhaps 140-165° F.) to the storagetemperature of 40° F. The longer the food takes to cool, the longer thefood will be at a temperature range conducive to the growth of harmfulbacteria and the like which can spoil the food and cause illness.

The commercial food industry, for example, will often use manual laborto take large volumes of hot food and place them in plastic bags forprotection and submerge the bags and food in ice baths to cool the foodfrom the cooking temperature to the storage temperature. This is a verycostly procedure given the energy and labor input that is required eachtime the procedure is undertaken. In addition, the bags are used tosubsequently reheat the food. This process of using bags involvesphysically handling the food at each bag iteration. It often takes morethan a four hour period to cool the food from the cooking temperature tothe storage temperature. In addition to the bags and the ice baths,quite often the food is broken down into smaller pans to facilitatecooling. Again, this results in a waste of labor, energy and food andresults in an increased possibility of cross-contamination. Manyjurisdictions have regulations that limit the time for this coolingprocedure and this must be monitored continuously.

In heating the food just before serving, time is also critical. It isdesirable to keep this time as short as possible to give the preparergreater flexibility in the timing of the final meal service. Further,the shorter the interval of time to heat the food, the less time thefood will be exposed to a temperature range conducive to the growth ofbacteria. Also, less energy is required to heat the product totemperature and less product is lost to burning or dehydration at theedges nearest the heat source due to non-uniform heating of the product.

A need exists for a process to more rapidly heat and cool food toprovide the advantages of a safer food service and to satisfy theapplicable regulations, reduce energy, labor and product loss due toinefficient thermal effects.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, an apparatus isprovided for rapidly changing the temperature of a mass of product. Theapparatus includes at least one input heat transfer element extendinginto the mass of product and at least one output heat transfer elementexposed to an ambient temperature environment to transfer thermal energybetween the input heat transfer element and the output heat transferelement.

In accordance with another aspect of the present invention, theapparatus is employed with a pan containing the mass of product. A lidis provided for the pan which has a plurality of slots therein. Theapparatus includes a plurality of input heat transfer elements formed asfins, the fins extending through the slots in the lid and into the massof product therein. The output heat transfer element is positionedexterior the lid. In accordance with another aspect of the presentinvention, the fins can be removable. The fins also can touch the bottomof the pan to enhance heat transfer.

The input heat transfer elements can extend from the top of the pandown, from the bottom of the pan upward, or horizontally from the sides.

The apparatus may be integral with the top closure of the pan or may beused with an expandable handle to facilitate removal of the apparatusfrom the pan.

Heat transfer can occur by conduction, convection and radiation.

A working heat transfer medium, either a solid, liquid or gas, can beutilized to improve the heat transfer.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the invention and its advantages willbe apparent from the following detailed description, when taken inconjunction with the accompanying drawings, in which:

FIG. 1A is a perspective view of a food preparation and storage deviceforming a first embodiment of the present invention;

FIG. 1B is an exploded perspective view of the food preparation andstorage device;

FIG. 2 is a plan view of the device of FIG. 1;

FIG. 3 is an end view of the upper portion of the device of FIG. 1;

FIG. 4 is a detail view of the exposed heat transfer fins of the device;

FIG. 5 is a side view of one of the fins used in the lower end of thedevice;

FIG. 6 is a side view of a modified fin used in the device;

FIG. 7 is an end view of a device forming a first modification of thedevice shown in FIG. 1;

FIG. 8 is a detail view of the device of FIG. 7;

FIG. 9 is a detail view of a fin used in the device of FIG. 7;

FIG. 10 is a detail view of a cooling fin used in the device of FIG. 7;

FIG. 11 is an end view of a second modification of the device of FIG. 1;

FIG. 12 is a cross-sectional view of FIG. 11 taken along line 12—12 inFIG. 11;

FIGS. 13A, B, C are fins used in the device of FIG. 11 of differentlengths;

FIG. 14 is a cross-sectional view of the fin of FIG. 13C taken alongline 14—14 in FIG. 13C;

FIG. 15 is a detail view of the fins of the device of FIG. 11;

FIG. 16 is an end view of a device cast, extruded, molded or machined asa unitary body;

FIG. 17 is a detailed view of a device having a hollow body and finscontaining a thermal transfer medium with thermal characteristicsoffering a high thermal capacitance and heat transfer rate;

FIG. 18 is an end view of a device having hollow fins and body and inletand outlet ports for passage of a coolant;

FIG. 19 is a detailed view of the device of FIG. 18;

FIG. 20 is an end view of a device having a hollow body and fins with aninlet and outlet port for passage of coolant which does not use aircooled fins;

FIG. 21 is an end view of a device incorporating a temperature monitor;

FIG. 22 is a cross-sectional view of the temperature monitor;

FIG. 23 is an end view of a removable handle used to grasp the device;

FIG. 24 is a graph of a freezer test with 17.5 pounds of refried beansin a 20° F. residential freezer unit;

FIG. 25 is a graph of a freezer test for 17.5 pounds of refried beans ina 20° F. industrial freezer unit;

FIG. 26 is a reheat test of 17.5 pounds of refried beans in a 450° F.industrial unit utilizing the device of FIG. 1A;

FIG. 27 is a graph of a cooling test for 17.5 pounds of refried beans ina pan using the device of FIG. 1A in a walk-in industrial refrigerationunit at 40° F.;

FIG. 28 is a graph of a cooling test for 17.5 pounds of refried beans ina pan using the device of FIG. 1A cooled in a walk-in industrialrefrigerator unit at 40° F;

FIG. 29 is a graph of a cooling test for 19.2 pounds of spaghetti saucein a pan utilizing the device of FIG. 1A in a walk-in industrialrefrigerator at 40° F.;

FIG. 30 is a cooling test of 17.5 pounds of refried beans in a panutilizing the device of FIG. 1A in an industrial freezer at 20° F.;

FIG. 31 is a graph of a cooling test for 17.5 pounds of refried beans ina pan utilizing the device of FIG. 1A in an industrial freezer unit at20° F.; and

FIG. 32 is a graph of test results of a cooling test for 19.2 pounds ofspaghetti sauce in a pan utilizing the device of FIG. 1A in anindustrial freezer unit at 0° F.-20° F.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the figures, and in particular to FIGS. 1A-6,there is shown a food storage and preparation device 10 forming a firstembodiment of the present invention. The device 10 is intended to beused with a food preparation and storage pan 15 as is commonly used inthe food service industry. For example, typical pans of this type mighthave horizontal dimensions of nine inches by twelve inches and a depthof about six inches. As will be described hereinafter, device 10 notonly can provide a lid for the container, but also provides for rapidcooling and heating of the food within the pan.

The device 10 can include a lid 12 which has a series of linear slotstherethrough. The lid 12 is designed to fit commonly used pan designsfound in the food industry today. In addition, the device 10 includes aheat transfer assembly 16 which includes a body 18 forming a pluralityof air contact fins 20 and a plurality of food contact fins 22. The foodcontact fins 22 are positioned on the body 18 to fit through slots 14 inthe lid 12 and enter the mass of food or other product within the pan 15on which the lid is positioned. If desired, the bottom edges 24 of thefood contact fins 22 can contact the bottom of the pan.

The heat transfer assembly 16 is preferably formed of a material havinga high coefficient of thermal conductivity. For example, the assembly 16and lid 12 can be made of aluminum, stainless steel, cast iron, copper,high thermally conductive plastics, polymers, polyimides, organic orinorganic structures, or other suitable material. The material can besandwiched or coated or a combination thereof provided that the heattransfer capability is satisfactory utilizing the preferred heattransfer characteristics of solid, liquid or gas.

As can be appreciated, the assembly 16 provides for more rapid heattransfer between the mass of food within the pan and the surroundingambient air. When the mass of food is being cooled from the cookingtemperature to the storage temperature, typically 40° F., the intimatecontact between the mass of food and the plurality of food contact fins22 provides for enhanced heat transfer from the food mass into theassembly 16. The heat transfer is rapid from the food contact fins 22into the body 18 and air contact fins 20, where the heat is rapidlydissipated by heat transfer to the ambient air. Similarly, when the foodis to be heated, such as by positioning the pan and assembly 16 in anoven, the ambient air temperature and incident radiation will rapidlyheat the air contact fins 20, conveying heat to the body 18 and foodcontact fins 22. Because of the intimate contact between the mass offood and the food contact fins 22, the heat is more rapidly transferredinto the mass of food than is possible without the use of the assembly16.

Among its many advantages, the device 10 will allow the cooling andheating rates of prepared foods to be shortened significantly. This willalso extend food shelf life and increase storage. The device willimprove performance within the health code guidelines and open thestorage performance envelope in terms of storage and preparation time.Health and handling hazards are reduced and the handling appropriationcosts of the food are reduced. Because the food industry has for yearsbeen in the process of standardization of pans, cooking apparatus andrefrigeration for food storage, the present device, which is readilyadaptable to present designs, reduces additional costs to a minimum.Other industrial and commercial applications of device 10 in such areasas cosmetics or pharmaceuticals would only require the scaling up ordown in size of the device along the design parameters of the invention.The device 10 is also passive in the performance of its function,requiring a minimum of human interaction and thereby limiting thecross-contamination of the product. As seen in FIGS. 5 and 6, shorterfood contact fins 22 a can be used for shallower pans while deeper foodcontact fins 22 b can be used for deeper pans. The fins 22 fit withinslots 26 (FIG. 3) formed in the bottom surface 28 of the body 18 whichallow different size fins to be mounted on a single design of body 18.The fins 22 can be welded, brazed, bonded, soldered, pinned, orotherwise attached to the body 18. The attachment can be permanent orremovable. The air contact fins 20 are preferably formed integral withbody 18 and also preferably are formed of a corrugated shape (FIG. 4)having a number of curved indentations 30 to increase the amount ofsurface area to enhance the heat transfer capability of the fins 20 tothe ambient air.

Clearly, other configurations of device 10 can be utilized. The heattransfer assembly 16 can be used without lid 12, if desired. Further,the configuration, size and number of fins 20 and 22 can be varied asdesired. Fundamentally, it is desired to have as much surface areacontact between food contact fins 22 and the mass of food as isnecessary to perform the desired heating or cooling function and to havesufficient surface area of air contact fins 20 to provide the desiredrate of heat transfer between the ambient air and the fins 20. Thisdevice allows for variation in the size, quantity, geometry andorientation of the heat transfer members to maximize performance alongthe principles enumerated herein. The modular concept allows for theswitching out of either the top finned segment or the entire device fora pre-frozen replacement to further facilitate the cooling of theproduct. The device 10 can be integral with the lid 12, or integral withthe pan 15. For example, fins 22 can extend upward from the bottom ofpan 15, or horizontally from the sides of pan 15.

A number of approaches to the device 10 can be taken. The device 10 canbe multi-sectional, involving separable modular components which allowsthe addition or removal of heat transfer elements based on the desiredend use and size of the pan. A two-piece design with lid can beutilized. A single unit involving a continuous extrusion of the finedassembly can also be made which would then be cut to the desired length.Preferably, the fins would be coated with an FDA approved coating, suchas provided by General Magnaplate, to facilitate cleaning and meetingfood handling requirements.

FIGS. 24, 25, 27, 28, 30 and 31 illustrate the cooling of refried beansusing the device 10. It will be noted that the beans are at storagetemperature within about two to three hours, rather than the up totwenty-four hours typically taken at the present time without use of thedevice 10 when done in a walk-in cooler with the same size pan.

FIGS. 24 and 25 show results for 17.5 pounds of refried beans in one panusing device 10 cooled in a 20° F. residential freezer unit. FIGS. 27and 28 show results for 17.5 pounds in one pan using device 10 ofrefried beans cooled in an industrial walk-in cooler at 40° F. FIGS. 30and 31 show results for 17.5 pounds of refried beans in one pan usingdevice 10 cooled in an industrial freezer at 20° F.

FIGS. 29 and 32 show various tests with spaghetti sauce by using device10. In these tests, 19.2 pounds of sauce was placed in a pan usingdevice 10. FIG. 29 is a test in a 40° F. industrial Unit and FIG. 32 isa test in a 0° F. to 20° F. industrial unit. FIG. 26 shows the advantageof reheating foods, such as beans, using device 10. The temperature ofthe beans rises more rapidly than otherwise would be possible to theserving temperature. FIG. 26 heated 17.5 pounds of refried beans in onepan using device 10 in a 450° F. industrial oven.

With reference now to FIGS. 7-10, a first modification of the inventionis illustrated as food storage and preparation device 50. A number ofelements of device 50 are the same as device 10 and are numbered withthe same reference numerals. In device 50, a body 52 is provided whichhas dove-tail slots 54 therein for receiving the food contact fins 56.The fins 56, in turn, have dove-tail ends 58 which fit within the slots54. If desired, the fit between fins 56 and body 52 can be a simplesliding fit to ease removal of the fins 56 from body 52 for easycleaning.

With reference now to FIGS. 11-15, a food storage and preparation device100 forming a second embodiment of the present invention is illustrated.Again, a number of elements of device 100 are the same as devices 10 and50, and are identified by the same reference numeral. In device 100, thebody 102 has a series of corrugated notches 104 to receive a foodcontact fin 106 a, 106 b or 106 c. The fins 106 a, 106 b and 106 c, inturn, have corrugated ends 108 to be received within the notches 104. Asshown in FIGS. 13A-C, the fins 106 a, 106 b, and 106 c can have variedlengths to adapt the device to a particular size pan, for example, 4inches, 6 inches and 10 inches in length to fit pans with these depths.As can be seen in FIGS. 12 and 14, both the body 102 and fins 106 a, 106b and 106 c have pin apertures 110 to receive a pin therein to lock thefins 106 to the body 102. The modularity also enhances cleaning andhandling characteristics.

FIG. 16 illustrates a device 200 which is formed as a unitary body whichcan be cast, extruded, molded or machined. In other regards, it isidentical to device 10.

FIG. 17 illustrates a device 220 which is formed with a hollow body 222containing cavity 224 and hollow food contact fins 226 defining cavities228 along their length. Cavities 224 and 228 are connected and thecavities can contain a material 230 with high heat capacity and heattransfer rate. The material 230 can be a solid, liquid or gas and can betransformed from a solid to a liquid or gas during the heat transferprocess.

FIGS. 18 and 19 illustrate a device 240 which has body 242 with cavity244 and food contact fins 246 with cavities 248. Again, cavities 244 and248 are connected. In addition, the body 242 has an inlet port 250 andan outlet port 252 opening through the exterior of the body into thecavity 244. The inlet port 250 can be connected to a source of heattransfer fluid, such as water or other liquid or gas material, whichenters port 250 and flows through the cavities 244 and 248 absorbingheat. The heated fluid or gas is then removed from the outlet port 252to a heat exchanger for reuse in the device 240 or disposed of. Device240 permits variation of the heat transfer characteristics of the deviceby selecting a desired heat transfer fluid flow rate and type ofmaterial.

FIG. 20 illustrates a device 260 similar to device 240 in utilizingcoolant flow therethrough. Because of the coolant flow, the air contactfins 20 are not utilized.

FIGS. 21 and 22 illustrate the use of a temperature monitor 280 in thedevice 10, but the monitor 280 can be used with any other devicedescribed herein. The temperature monitor gives a visual indication whena portion of the device or the material being heated or cooled hasreached a certain temperature. With reference to FIG. 22, the monitor280 can be seen to include a housing 282 into which is fit an indicatingpin 284, a return spring 286 and a shape memory alloy spring 288. A cap290 confines the pin and the springs within the housing 282. Below adetermined temperature, the return spring acts between the cap 290 andridge 292 on pin 284 to maintain the pin retracted within the housing.At the predetermined temperature, the shape memory alloy spring 288increases in length, compressing the return spring 286, and urging end294 of the pin 284 outside of the housing to provide a visual indicationthat the predetermined temperature has been achieved. For example, thetemperature monitor 280 can be designed to actuate at about 140° F. or,to react when the temperature is about 40° F.

With reference to FIG. 23, a removable handle 310 can be employed toassist in placing and removing the device 10 and other devices describedherein. The handle 310 includes a first arm 312, and a second arm 314connected together by a pivot 316. Each arm has an in turned lip 318 topass around the bottom of the body of the device to allow the device tobe moved.

Although the present invention and its advantages have been described indetail herein, it should be understood that various changes,substitutions and modifications of parts and elements can be madewithout departing from the spirit and scope of the invention as definedby the appended claims.

I claim:
 1. A method for rapidly changing the temperature of a mass ofproduct, comprising the steps of: placing a plurality of input heattransfer elements within the mass of product; and exposing a pluralityof output heat transfer elements in thermal contact with the pluralityof input heat transfer elements to an ambient temperature environment totransfer thermal energy between the product mass and ambient temperatureenvironment, heat flow being equally effective from the input heattransfer elements to the output heat transfer elements as from theoutput heat transfer elements to the input heat transfer elements toallow equally effective cooling or heating of the product mass.
 2. Themethod of claim 1 further comprising the step of inserting a pluralityof said input heat transfer elements within the product simultaneously.3. A method for rapidly changing the temperature of a mass of product,comprising the steps of: placing a plurality of input heat transferelements within the mass of product; exposing a plurality of output heattransfer elements in thermal contact with the plurality of input heattransfer elements to an ambient temperature environment to transferthermal energy between the product mass and ambient temperatureenvironment; and removing said plurality of input heat transfer elementsfrom said plurality of output heat transfer elements to facilitatecleaning.
 4. The method of claim 1 further comprising the step ofinserting said plurality of input heat transfer elements through a slotformed in a lid for a pan containing the mass of product to insert saidplurality of input heat transfer elements into the mass of product. 5.The method of claim 1 further comprising the step of passing a heattransfer medium through a hollow interior of said plurality of inputheat transfer elements to transfer heat to the heat transfer medium. 6.The method of claim 1 further comprising the step of grasping theplurality of input heat transfer heat elements with a removable handle.7. The method of claim 1 wherein the step of placing said plurality ofinput heat transfer elements within the mass of product includes thestep of placing the plurality of input heat transfer elements within amass of food.
 8. The method of claim 1 further comprising a step ofproviding a visual indication when the at least one input heat transferelement has achieved a predetermined temperature.
 9. The method of claim1 further comprising the step of orienting said plurality of input heattransfer elements and said plurality of output heat transfer elementsgenerally parallel the direction of insertion of the plurality of inputheat transfer elements within the mass of product.
 10. The method ofclaim 1 wherein the plurality of input heat transfer elements arehollow, forming chambers, the chambers being connected by a manifold,the step of placing the plurality of input heat transfer elements withinthe mass of product further comprising the step of permittingcirculation of a thermal transfer medium between the chambers andmanifold.
 11. The method of claim 1 wherein the step of placing aplurality of heat transfer elements within the mass of product includesthe step of placing a plurality of input heat transfer elements formedof a coated heat conductive material within the mass of product so thatthe mass of product contacts the coating.
 12. A method for rapidlychanging the temperature of a mass of pre-cooked food, comprising thesteps of: placing at least one input heat transfer element within themass of pre-cooked food; and exposing at least one output heat transferelement in thermal contact with the at least one input heat transferelement to an ambient temperature environment to transfer thermal energybetween the food and the ambient temperature environment so that thetemperature of the food is changed 100 degrees F. within four hours,heat flow being equally effective from the input heat transfer elementto the output heat transfer element as from the output heat transferelement to the input heat transfer element to allow equally effectivecooling or heating of the food mass.
 13. The method of claim 12 whereinthe food is cooled from 140 degrees F. to 40 degrees within four hours.14. The method of claim 13 wherein the food is cooled from 140 degreesF. to 70 degrees F. within two hours and cooled from 70 degrees F. to 40degrees F. within two additional hours.
 15. The method of claim 12wherein the food is heated from 40° F. to at least 160° F. within onehour.